If you attended an SEG Annual Meeting in the 1980s, pick any year after 1983, and you walked into the exposition hall, you would have heard a unique sound. It was a distinct "boom," an unobtrusive signal clearly audible above the background noise. The source of the sound was Earnest R. (Harry) Harrison's sleeve air gun, firing every 10 seconds at a twentieth of its normal operating pressure in a transparent water tank. "The heartbeat of the SEG," someone called it. To be aware of the contribution of another participating geophysicist at the convention, you would have to visit a specific exhibit, or a lecture hall at a specific time, but to be aware of Harry Harrison's contribution, all you needed to do was to stand anywhere in the exposition hall, and you'd hear it. In a sense, that models Harry's contribution to geophysics. Today, his sleeve air guns are used nearly everywhere marine seismic exploration for hydrocarbons is conducted.
     A native Houstonian, Harry graduated from Texas A&M University with a degree in mechanical engineering in 1964 and spent his early years working on safety relief valves. Some were used in the rockets that took U.S. astronauts to the moon. He joined Texas Instruments in 1969 and became involved with the air gun development program TI supported for its subsidiary, Geophysical Service Inc.
     Although he is being honored today for his contributions to geophysics through the development of sleeve air gun technology, many of his innovations that helped to make the sleeve air gun so successful were developed on conventional air guns. Marine source arrays use many guns and at the outset of this technology there were two aspects of concern. Firstly, did all the guns fire properly when triggered and, secondly, did they all fire on time? Harry Harrison solved both these problems by designing a magnetic sensor that would not only determine if each gun had fired but through automatic computerized interrogation, precisely when. It was a brilliant solution of elegant simplicity. Also, during this period, Harry developed a valve that, when incorporated in the gun chamber, reduced the air consumption by 40%.
     In 1982, Harry unveiled the sleeve air gun. It was another elegant Harrison design that cut the number of components by half. The unit was inherently more stable and reliable. The well-proven firing and timing systems transferred to the new gun and its popularity took off.
     Harry Harrison has authored and coauthored 15 U.S. patents with two more pending. He was an elected senior member of the technical staff of both Texas Instruments and Halliburton Energy Services and later became a Distinguished Member of the technical staff of Halliburton an elite group of only eight people. Harry a quiet unassuming gentleman with immaculate southern courtesy, a creative engineer, and the finest colleague and friend one could have.
     At one SEG convention, I found myself at lunch with Harry and two other marine source specialists, Adrian Pascouet of Seismic Systems and Paul Chelminski of Bolt Technology. As I sat there listening to their conversation and watching the delegates milling around the exhibits, it occurred to me that between Harry, Adrian, and Paul, there was probably more marine source expertise at that table than at the rest of the SEG put together. The delegates seemed oblivious of this fact. With this award to Harry Harrison, the SEG delegates need be oblivious no more.

     W. Rodney Cotton